How will the melting of ice at the poles affect ocean currents and monsoons? Will the weather be more capricious?

Global warming has become a hot topic. The global warming has not slowed down at all, and the climate of the earth has been changing, but how this change happened and what role we humans played in this process is still an unsolved mystery.

The 1990s was the hottest decade on record.

There is no doubt that our planet is getting warmer. In the last century, the global average temperature climbed about 0.6 degrees Celsius. In the northern hemisphere, the thawing period of ice and snow in spring is 9 days earlier than that before 150, but the start time of frost in autumn is about 10 days later.

The 1990s was the warmest decade since the mid-Kloc-0/9th century when temperature records began. The hottest years recorded are: 1998, 2002, 2003, 200 1, 1997.

2. By the end of this century, the global temperature will rise by 1.6 to 5.5 degrees Celsius.

The Arctic Climate Impact Assessment (ACIA) report recently made by many countries claims that the average temperature in Alaska, western Canada and eastern Russia has increased by 3 to 4 degrees Celsius in the past 50 years, almost twice the global average. The average temperature in Alaska (the northernmost city in the United States) has increased by 2.5 to 3 degrees Celsius in these 30 years.

The United Nations Intergovernmental Panel on Climate Change (IPCC) predicts that the global temperature will rise by 1.6 to 5.5 degrees Celsius by the end of this century.

3. Every 654.38+million years is a global cycle of alternating cold and warm.

In the past millions of years, the earth has been undergoing periodic alternating changes of cold and warm, about once every 654.38+ million years. Alternating activities are mainly controlled by sunlight, and the amount of sunlight on the earth is determined by its orbit and the orientation of celestial bodies.

These changes happened very quickly in the past, and scientists hope to get more information about today's climate change from the analysis of these changes. Glaciers covered most parts of North America and Europe from about 70,000 to 65,438 thousand+0./kloc-0. 5 thousand years ago, but during that time, sudden and sometimes drastic climate changes still took place. The Greenland ice core shows that the surface temperature in this area increased by 9 degrees Celsius during 10.

Where can scientists find clues about past climate change? Legend has it that some clues can be found in some residual materials, such as flowing ice, moraine, pollen-rich soil, stalagmites, coral reefs, coral trees and marine sediments that produce microscopic biological shells. Moreover, human history also provides some clues, such as records of some ancient characters and inscriptions, records of gardening and wine making, and logbooks of some famous maritime events.

4. Arctic sea ice area shrinks by 9% every 10 year.

The rising temperature has a serious impact on the Arctic ice layer, which plays the role of "air conditioner" at the top of the world. Since 1978, the arctic sea ice area has shrunk by 9% every 10 year, and it is getting thinner and thinner.

ACIA predicts that half of the Arctic summer sea ice will melt by the end of this century, and the Arctic temperature will rise by 4 to 7 degrees Celsius.

For a long time, the thick ice bed in Greenland has accumulated enough meltwater to raise the sea level by about 7 meters. The ACIA climate model predicts that the main ice bed melting event will run through the whole 2 1 century.

Many dissolved glaciers in the world block a lot of fresh water. Montana National Glacier Park had 150 glaciers when it was completed in 19 10. However, due to the rapid shrinkage of glaciers, there are now less than 30 glaciers left. Tropical glaciers are facing more trouble. The snow on the 5895-meter-high summit of Mount Kilimanjaro in Tanzania has melted 80% since 19 12, and will disappear completely in 2020.

The sea level rose by 10 to 20 cm on average in the last century.

In the long geological history of the earth, the sea level has risen and fallen many times. According to the IPCC survey, the global average sea level rose by 10 to 20 cm in the last century.

The annual report of IPCC 200 1 points out that the sea level may rise by 10 to 89 cm by the end of this century. This rise may have a major impact on coastal residents. A 50 cm rise in sea level will directly cause the coastline to retreat by 50 meters.

About 65438+ billion people in the world live within the average sea level 1 meter. A sea level rise of only 10 cm may flood many South Pacific islands, and Florida and Louisiana in the United States will be in danger. The highest altitude of the Indian Ocean country Maldives is only 2.5 meters, and a breakwater building around the capital Male was attacked by high tide. A polar bear walks on the rocky ground in Wagga Bay, Canada. Polar bears are the most attractive large animals in the Arctic, and are facing the serious threat of global warming.

6. Global warming will lead to more frequent extreme weather events.

Ocean circulation system is called ocean conveyor belt, which mainly regulates global temperature by transferring tropical heat to all parts of the earth. Global warming may change the balance of this system by melting glaciers and injecting fresh water.

Climate models show that global warming may lead to more frequent extreme weather conditions. Strong hurricanes and violent storms will also threaten coastal communities, and heat waves, fires and droughts may become more common.

7. Greenhouse gases are increasing rapidly, and millions of plants and animals are on the verge of extinction.

Since 65438+1960s, with the improvement of industrialization and the reduction of forest area, the content of carbon dioxide in the atmosphere has increased by one ten thousandth, and the temperature in the northern hemisphere has also increased. Since the 1950s, the increase of temperature and greenhouse gases has become more intense.

Water vapor is the most important greenhouse gas. Carbon dioxide, methane and nitrous oxide also contain heat and will keep the balance of the earth's mild climate in cold areas. Human activities, such as burning fossil fuels and deforestation, quickly lead to the concentration of these gases, even exceeding the speed at which plants and oceans absorb them. These gases have accumulated in the atmosphere for many years. Even if the release of these gases is completely stopped now, it is impossible to stop the warming trend caused by them.

A recent study shows that by 2050, human-induced temperature rise will intensify, and carbon dioxide and other greenhouse gases emitted into the air will make more than one million species of land plants and animals extinct.

8. The Arctic and Antarctic bear the brunt.

In the Arctic, the effects of climate warming have already appeared. Local communities along the coast report that the shorter and shorter seawater ice age can no longer regulate ocean storms and their destructive coastal erosion. When the melting of permafrost brings serious damage to roads and other infrastructure, the increase of melting snow and ice also leads to the rise of rivers, and some residential communities have to move away from the historical coastline.

The disappearance of sea ice will destroy some species that have adapted to this environment, such as polar bears, Arctic ringed seals and Antarctic penguins.

9. Biological physiological time is advanced.

The study found that the flowering time of many European plants was one week earlier than that in 1950s, but the defoliation time was delayed by about five days.

Biologists report that many birds and frogs breed earlier than normal. The analysis of 35 non-migratory butterflies shows that two thirds of them extend 3.5 to 240 kilometers to the north compared with decades ago.

With the disappearance of some algae and attached organisms, and the water temperature rising above 29.5 degrees Celsius in calm and sunny days, coral reefs all over the world show a trend of whitening. Scientists worry that rapid climate change may inhibit the adaptability of many species in this complex and interdependent ecosystem.

10, incomplete global warming is negative.

The consequences of global warming are not all negative. The heat may tilt to some cold areas, which will benefit the huge agricultural areas in the northern hemisphere. Transportation and resource development in the Arctic will also become more feasible.

But many species, including humans, will be hit hard. The most vulnerable people are the residents living in the northernmost part. Those people live along the coast and on farms with little surplus grain. They will have to endure the capricious attacks of climate change.

Due to global warming, the Arctic sea ice is gradually melting, and the Antarctic ice shelf has collapsed. Meteorologists said in an interview with reporters today that although the South Pole and the North Pole seem to be far away, human activities are already affecting the climate change at the poles of the earth, and the changes in polar climate and atmospheric environment are also affecting the weather and climate in China.

Lu Longhua, a researcher at China Institute of Meteorological Sciences, said in an interview today that cold air from the Arctic will have an impact on China in winter, and the weather and climate events that cause disasters in China are mostly related to cold and warm air activities and their abnormal activities. At the same time, the cold, warm and sea ice conditions in the Antarctic or Arctic may also affect the disastrous weather in summer in China.

At present, the North and South poles are the least affected by human activities and environmental pollution in the world, but human activities are already affecting the climate change at the poles of the earth. Lu Longhua said that great changes have taken place in the Arctic in the past few decades. The latest research shows that the extent of Arctic sea ice decreases by about 3% every ten years, and the thickness of Arctic sea ice decreases by 3% to 5% every ten years. In the past 100 years, the global temperature has risen by 0.6 degrees Celsius. In the twentieth century, the temperature on the Arctic land rose by five degrees Celsius.

The meteorologist said that studies have confirmed that if the Arctic sea ice melts at the current rate, all the Arctic sea ice will disappear after 80 to 100 years. This will inevitably lead to the frequent occurrence of extreme disastrous weather events such as global temperature rise, drought and flood.

According to the assessment report "Climate Change 2007: Basis of Natural Science" issued by the United Nations Intergovernmental Panel on Climate Change, by the end of 2 1 century, the global surface temperature is expected to increase by an average of 1. 1 to 6.4 degrees Celsius under various greenhouse gas emission scenarios. If the global average warming trend of 1.9 to 4.6 degrees Celsius continues, it will eventually lead to the complete melting of the Greenland ice sheet, which will lead to a sea level rise of about seven meters. Even more frightening is that more than 90% of the world's ice is in the Antarctic. If the Antarctic ice sheet melts completely, the global sea level will rise by 60 meters.

"This means that not only the small islands in the Pacific Ocean, but also the southeast coast of China, including Shanghai, will be flooded." The climate expert particularly stressed that this is only a "if", but if human beings don't stop destroying the earth, all this is not impossible to become a reality.

Some scientists have pointed out that the climate warming in recent 50 years is mainly caused by the warming effect of greenhouse gases such as carbon dioxide emitted by human beings using chemical fuels. "Global warming is influenced by both human activities and natural factors, but human beings have only one earth. If it is destroyed, it is difficult to recover. Therefore, from now on, we should reduce the damage of human activities to the earth and reduce greenhouse gas emissions.